Using the medium-frequency welding system with servo-controlled welding feed specially developed for door handle production, it is possible to seal the tube ends of door handles from steel and stainless steel in a high quality and economical process. This is also possible in particular with small batch sizes and a wide range of parts, due to the short set-up times with workpiece changes without auxiliary tools as well as a high degree of production flexibility due to the ATEC rapid change system for different workpiece retainers.